Carburetor for internal-combustion engines



Oct. 21 1930. G LOUTZ 1,778,904

CARBURETOR FOR INTERNAL COMBUSTION ENGINES Filed April 26 1926 PatentedOct. 21, 1930 GEORGES LOUTZ, OF BRUSSELS, BELGIUM,

PATENT OFFICE assmnon, BY iuEsNn ASSIGNMENTS, 'ro

THEL'MA CARIBURATOR COMPANY SOCIETE ANONYME, OF BRUSSELS, BELGIUM, A-

GOBPORATION 0F BELGIUM GARBUBETOR FOR INTERNAL-COMBUSTI ON ENGINESApplication filed April 26, 1928, Serial No.

This invention relates to carburetors for internal combustion engines.

The object of the invention is to provide a carburetor which is simplein structure, economical to manufacture, and efficient in operation. 1

A further object is to provide a carburetor of the nature referred towhich is automatically actuated and controlled by the suction action ofthe engine to secure and maintain the proper economical feed of the fuelin the desired proportion according to the speed of the engine.

A further object is to provide a carburetor in which a desirable excessof fuel is automatically supplied to the engine temporarily in startingup the engine from rest.

A further object is to secure and maintain the required admixture offuel and air to constitute the explosive charge according to the desiredspeed of operation of the engine.

A further object is to dispense with the float control of the supply offuel now in common use in carburetors.

Other objects of the invention will appear more fully hereinafter.

The invention consists substantially in the construction, combination,location and relative arrangement of parts, all as will be more fullyhereinafter set forth, as illustrated in the accompanying drawing, andfinallypointed out in the appended claims.

In the accompanying drawing :5-

Fig. 1 is a view in central longitudinal section of a carburetorstructure embodying the principles of my invention.

Fig. 2 is a view in section on the line 2, 2, Fig. 1 parts broken off,showing the relation of the parts with the auxiliary air controlthrottle in wide open-position.

Fig. 3 is a view similar to Fig. 2 with the throttle shown in almostclosed position for slow running of the engine;

The same part is designated by the same reference numeral throughout theseveral views.

Inorder to effect the quick easy starting up of a motor engine from restit is desirable to supply, temporarily, an excess of motor fuel to theengine. It is among the 104,783, and in Belgium October 10, 1925.

motor fuel, which, under suitable valve control, is in communicationwith the jets or orifices through which the fuel is sup lied into amixing space or chamber for a 'xture therewith of air in the requiredproportion to form the explosive charge. The valve which controls thesupply of fuel from the reservoir or storage chamber to the mixingchamber, in one form of embodiment of the principles involved, isdisposed to operate after the manner of a plunger in the fuel storagechamber or reservoir, so that when the plunger valve is suddenlyoperated to open up the communication between said reservoir and thecharge mixing chamber in starting the engine from rest, said valvedisplaces the fuel contained in the reservoir and forces the same, intemporary excess, into the charge mixing chamber.

To effect this operation of the valve I connect the same so as to beinfluenced by the sudden inrush of air into the mixing chamber due tothe suction action of the engine in starting up. I also provide meanswhereby the continued suction action of the engine, in the continuousoperation thereof, is utilized to control the position of the valve withrelation to its function of controlling, the supply of fuel tov themixing chamber in accordance with the desired speed of theengine, and tomaintain such supply uniform for any articular speed, thus utilizing thevalve an the engine suctionin co-action with each other to accomplishthe double function of temporarily supplying an excess of fuel ininitially starting up the engine, and also of controlling the economicsupply thereof for contin- .uous operation and according to the desirespeed, thereby securing a quick easy starting of the engine and economyof fuel consumption in continuous operation thereof.

It is also within the contemplation of my invention to provide means, ifdesired, or required, to supply additional air to the explomixingchamber b the suction action of the engine I restrict t e area of thepassage for the air in the vicinity of the jets-or orifices throughwhich the fuelis supplied into the mixing chamber. This ma beaccomplished in various ways. In accor ance with my invention I proposeto employ a choke device which is mounted in the mixm chamber anddisposed in such relation to the fuel jets or orifices as to produce arestricted passageway for the indrawn air there ast, and in order toaccommodate the car uretor device to various types and makes of motorengine, I provide for the adjustment of the choke with relation to thefuel jets or orifices so as to vary the location of the greatestrestriction of the air passageway with reference to the fuel jetsaccording to the character of the motor engine in connection with whichthe carbuac retor is to be employed.

In the structure shown for carrying out 1 my invention, in oneillustrative embodiment wall of member 4 with a mixin thereof; I providea tubular member 4,

formed with an enlargement of its axial bore .at the inner end thereofto constitute a fuel stora e chamber or reservoir 7. This storage amberis formed with an extended portion 41 of restricted area whichcommunicates through jets or orifices 5, through the chamber 15.

An annular valve seat 13 is ormed in the bore of member 4 at a pointintermediate the reservoir or fuel storage chamber 7, and the extension41 of said chamber. The fuel 'supply hasaccess to the storage chamber 7through a conduit 6, which communicates therewith and with a fuel supplypipe connection 18. A needle valve 17 controls the supply of fuel fromthe supply ipe connection to the conduit 6. Dispose in the fuelreservoir or chamber 7 is the valve 8, the stem 9 of which extends throuh the extension 41 of chamber 7 and throug the portion 10 of the tubularmember 4, as a guide; The valve 8 is exteriorly ta ered so as to coactwith valve seat 13 to c ose or to open it more or less, according totheextent of movement of said valve towards and from said seat. Thevalve 8 constitutes, in effect, a plunger which moves freely in chamber7, so that when said valve is suddenly moved from its seated position inthe valve seat 13, which is its normal position when the motor engine isat rest, the head of said valve moves" through the chamber 7 anddisplaces the fuel supply of fuel.

contained or stored up therein, thereby forcing such fuel into theextension 41 of chamber 7 and through the jets or orifices 5. Thisoperation supplies the temporary excess of fuel to the engine instarting up thelatter from rest, since, as will presently be exaplained, the valve 8 is suddenly unseated by the suction action of theengine in starting up. This excess supply of fuel is only temporary forthe reason that when the engine is once started the valve 8 assumesainore or less steady 'osition, being shifted therefrom only when t espeed of the engine is varied in which case the movement thereof inchamber 7 is not suflicient to cause any appreciable excess flow of fuelthrough the ets or orifices. Mounted on the extended end 42 of the valvestem 9 is a member 11, shown in this instance in the form of a disc, andwhich, when the engine'is at rest is heldseated against a shoulder 14 ofenclosing casing 31. Said member 11 is so heldyieldingly by means of aspring 12, and when in this position the valve 8 is held in its valveseat 13. The annular seating surface 14' encom asses the passage throughwhich the air is rawn into and through the casing by the suction actionof the engine, and hence the member 11 is subjected to the action of theentering air pressure. This pressure tends to move said member 11,against the yielding resistance of the spring 12, thereby shifting andmaintaining the valve 8 out of its seat 13 to an extent dependent uponthe degree of the pressure exerted thereon by the incoming air, that is,de ent upon the speed at which the engine is operating,,thus securinggreat economy in fuel consumption. It is this movement of member 11 andvalve 8,-in the illustrat've form of my invention as shown, suddenlyimposed in starting up the engine, which effects temporarily the supplyof a surplus of fuel to secure quick easy starting of the engine.

It is desirable in carburetor devices to utilize the current of airdrawn in by the suction action of the engine to aid in effecting the Toaccomplish this function in a simple effective and economical manner thecurrent of in-drawn air is caused to sweep past the jets or orifices 5,thereby creating a siphonic negative pressure on the fuel and hencedrawing the fuel through said jets or orifices and into and carrying italong with the air to form the explosive charge. To secure the bestresults it is desirable to increase the'velocity of the indrawn air inthe region where it passes the jets or orifices. I accomplish this bymounting an annular choke member 16 within the casing 31. This chokemember 16 is in :he form of a ring or sleeve which encompasses thetubular member 4, and its least internal diameter is disposed in suchrelation to said member 4, and the jets or orifices 5, therein as tocause a restriction'at that point in the area of the passage throughwhich the air is drawn. This secures the desired increase in velocity ofthe air flow past the orifices or jets 5, and hence the desired supplyof the fuel, according to 5 the desired speed of the engine. Since thesuction action exerted by-engines is dependent upon the size and len thof stroke of the pistons, and since these actors vary in engines ofvarious makes, I pro ose, in accordance with my invention to a apt thecarburetor to use on engines of various makes by mounting the chokemember 16 so as to be replaceable or adjustable with relation to thejets or orifices so that the position thereof may be varied to suit therequirements of engines of the various makes. In the arrangem'ent shownthe choke 16 is held in its replaceable or adjusted position by means ofthe screw 40, by means of which the casing 31 is retained in place. I

The explosive charge passes from the mixing-chamber of the carburetor tothe engine. This maybe accomplished in various ways. As shown thispassage is through the connections 19, 20 to the engine intake. Ifdesired, or required, the usual throttle or similar device 21 may bedisposed in this connection and actuated and controlled in the usualmanner,

as, for example, from the accelerator through an arm 22. g

It may sometimes be desirable to dilute an over-rich explosive charge,in order to secure better operation of the engine and a more economicalconsumption of fuel. This result may be accomplished by providing forthe sup ly of additional or auxiliary air to the exp osive charge in itspassage to the engine. Such additional or auxiliary air may be suppliedin various ways. Ihave shown a simple arran ement wherein the throttlemember 21 throttle member 21 is mounted to rotate within a casing 24 andis rovided with a seriesof annularly dispose passages 25, adapted to bebrought into register with co-operating ports 27 formed in adjustablymounted stationary cover plates 30, disposed at opposite sides of thethrottle member 21. If desired the registering passages 25, and ports27, one or the other, may be elongated as indicated in dotted lines inFigs. 2 and 3, so that, when the member 21 is rotatively movedrelatively to the cover plate, the registering areas of the passages andports are gradually increased or diminished as the case may. be. Thecover plates may be held in their adjustable position in any suitableway, as for example, by means of the screws 26. Thus the supply ofauxiliary or additional air into the passage 28 traversed by theexplosive mixture in its travel to the engine is controlledautomatically by the manipulation of the throttle by the driver, therebyeffectively controlling the character of the mixture supplied to,

the engine. It is quite obvious that other specific arrangements may beemployed to secure the supply of additional air.

Having no set forth the objects and'nature of my inven tion andapractical structure embodying the principles thereof, What I claim asnew and useful and of my own inventions, and desire to secure-by LettersPatent is 1. In a carburetor for internal combustion engines, a. mixingchamber having inlet and outlet openings, a fuel chamber in said casingin communication with said mixing chamber through a series of fueldischarge nozzles and a passage, a fuel control valve longitudinallymovable in said fuel chamber, said valve having an enlarged endprojecting into said fuel chamber and its other end projecting into saidmixing chamber, a suction operated disc on the projecting end of saidfuel control valve and arranged in the inlet opening of said mixingchamber, and a spring for normally causing said fuel control valve toclose said passage, the enlarged end of said fuel control valve actingas a plunger during starting to force excess fuel from said fuel chamberthrough said passage and nozzles into said mixing chamber and duringrunning to maintain a steady flow of fuel varying in quantity inaccordance With the speed of the engine.

2. In a carburetor a casing having a mixing chamber communicating withthe outer air, with a fuel supply and with the engine a valve actuatedby the intake of air to and through the chamber to control the supply offuel to said chamber, a throttle to control the supply ofthe explosivecharge to the engine,

and means actuated by said throttle for controlling the supply ofadditional air to -the charge at a point between-the mixing chamber andthe engine.

3.. In a carburetor, a casing'having a mixing chamber, a fuel casingdisposed centrally in the mixing chamber having a fuel reservoir formedat its inner end and a series of radial discharge nozzles formedoutwardly of the reservoir, a longitudinally adjustable fuel controlvalve adapted to control the discharge of fuel through the radialnozzles and operating in the fuel reservoir, and a suction operatedvalve comprising a disk supported solely by the outer end of the fuelcontrol valve adapted to open the fuel valve to supply fuel into themixing chamber directly in accordance with the suction produced in themixing chamber.

4. In a carburetor, a casing having a mixing chamber, a fuel casingdisposed longitudinally in the center of the mixing chamber formed witha fuel reservoir in its inner end and a series of radial dischargenozzles arranged outwardly of the reservoir, a fuel control valvelongitudinally adjustable in the fuel casing and having an enlarged headwithin the fuel reservoir adapted to control the delivery of fuelthrough the discharge nozzles, and a suction operated disc fixed on theouter end of the fuel valve and supported solely thereby adapted toautomatically operate the fuel valve to supply fuel to the mixingchamber directly in accordance with the suction produced therein.

5. In a carburetor, a casing having a passage therethrough forming amixing chamm ber, said passage communicating with outer air and with theengine, whereby air is drawn into and through said passage by enginesuction, a member disposed longitudinally in said passage forming a fuelsupply chamber and having a plurality of radial fuel jets establishingcommunication between said passage and said fuel supply chamber,-a valvestem slidably mounted in said member having an enlarged head forming a-valve for controlling the flow, of fuel from said fuel supply chamber,a needle valve for controlling the fuel supply to said fuel supplychamber, disc means mounted on said valve stem and disposed in saidpassage for controlling the valve under the suction action of theengine, a spring for resisting the movement of the disc means, athrottle valve in vsaid passage for controlling flow of air to theengine and an inlet valve controlled by said throttle valve forsupplying additional 'air to the mixture after mixing.

In witness whereof I aflix my signature. GEORGES LOUTZ.

